package cn.fayang.basic.interceptor;

import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.data.redis.core.RedisTemplate;
import org.springframework.stereotype.Component;
import org.springframework.util.StringUtils;
import org.springframework.web.servlet.HandlerInterceptor;

import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.PrintWriter;
import java.util.concurrent.TimeUnit;

@Component
public class LoginInterceptor implements HandlerInterceptor {
    @Autowired
    private RedisTemplate redisTemplate;

    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        //1.从请求头中获取 U-TOKEN
        String token = request.getHeader("U-TOKEN");
        if(StringUtils.hasLength(token)){
            //3.根据U-TOKEN从redis中获取登录信息
            Object loginTmp = redisTemplate.opsForValue().get(token);
            if(loginTmp != null){
                //刷新过期时间
                redisTemplate.opsForValue().set(
                        token,
                        loginTmp,
                        30,
                        TimeUnit.MINUTES
                );
                return true;//登陆了 放行
            }
        }
        //2.滚去登录
        response.setContentType("application/json;charset=utf-8");
        response.setCharacterEncoding("utf-8");
        PrintWriter writer = response.getWriter();
        writer.write("{\"success\":false,\"message\":\"noLogin\"}");
        writer.flush();
        writer.close();
        return false;//阻止放行

    }
}